1080ti SLI setup with 4x 34" curved moniors

[Kicksome]

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If you want the full available power of each GPU, then you'd want to split them up between the monitors, but that also comes with drawbacks.

What sort of drawbacks? I'm just curious if there are other drawbacks besides you won't get better than single card performance on one monitor? Or is there some sort of CPU/Memory/Windows issues when it has to switch between two video cards. I could imagine spanning a single instance of a game on multiple monitors that are on two video cards (non-sli'd) would incur some sort of penalty, but I didn't plan on that.

[MiRai]

What sort of drawbacks? I'm just curious if there are other drawbacks besides you won't get better than single card performance on one monitor? Or is there some sort of CPU/Memory/Windows issues when it has to switch between two video cards. I could imagine spanning a single instance of a game on multiple monitors that are on two video cards (non-sli'd) would incur some sort of penalty, but I didn't plan on that.

You would need to build a Window Layout around the fact that you shouldn't be swapping game clients between monitors because they'll incur a penalty in performance.

If a game client starts up on a particular monitor, then the GPU attached to that monitor is the one that is rendering that specific game client. If that game client moves to another monitor (e.g. if your window layout uses cross-monitor swapping), then the GPU that it started off attached to is no longer going to be able to render it on another screen which is attached to a different GPU, and therefore it is now being rendered through software rather than hardware, which is where a drop in performance is likely to be seen.

On the other hand, when using SLI you don't get 200% of two GPUs, or 300% of three GPUs, and there are normally diminishing returns when using a multi-GPU setup to render, but you can still use a multi-monitor layout and swap between monitors.

The choice is yours.